ABSTRACT
The long-term success of any wetland restoration or creation project is, to a very large extent, dependent upon restoring, establishing, or developing and managing the appropriate hydrology. Wetland hydrology (depth, period, and duration) determines abiotic factors such as water availability, nutrient availability, aerobic or anaerobic soil conditions, soil particle size and composition, and related conditions including water depth, water chemistry (pH, Eh), and water velocity. In tum, biotic components, especially plants, influence water gains through interception of precipitation, water losses through evapo-transpiration, as well as depth, velocity, and circulation patterns within the system. Plants influence water movement and even depth because vegetative resistance, "roughness", can create a slope to the water elevation. Water may mound in upstream areas to provide the necessary head to drive water through dense stands of downstream vegetation. In rare circumstances, notably beaver and alligators, wetland animals may have significant effects on system hydrology and even a large number of muskrat houses and feeding platforms in a prairie marsh or "chimneys" built by a large population of crayfish may have substantial though usually temporary effects.
